This invention relates to a reinforcement stirrup made of wire material for use in masonry, comprising an essentially flat support section and at least one flat stirrup leg which, when the reinforcement stirrup is in use, extends essentially vertically up from the support section for inclusion in a joint between constructional elements, as well as positioning means or element for an essentially horizontally extended main reinforcement, which means, when in use, extend from the plane of the support section and lie essentially outside this plane and extend in a direction opposite to that of the stirrup leg, whereby the plane of the stirrup leg intersects the plane of the support section within the bounds of the support section, and whereby the positioning means are formed by a hook with the stem of the hook lying in the plane of the support section and the arm of the hook extending essentially parallel to the support section.
Such a reinforcement stirrup is already known from DE-U-29713212.
Said publication describes a reinforcement stirrup of the kind referred to in the introduction, said stirrup comprising one stirrup leg for inclusion in the joint between two bricks, which are to be laid adjacent to one another, with the support section resting upon the upper surface of the two adjacent bricks. The positioning means mentioned in the introduction are used to position the additional main reinforcement in relation to the reinforcement stirrup, as, for example, an essentially horizontally disposed reinforcement that runs between courses of laid bricks and is commonly used to reinforce masonry to such an extent that, for example, the use of a lintel in a frame is rendered unnecessary, the reinforced masonry here effectively replacing such lintel.
The reinforcement stirrup of the type known in the prior art procures usable results, which nevertheless involve certain disadvantages.
The fitting of the additional main reinforcement after the reinforcement stirrups have been fitted is not easy and requires either that the reinforcing elements be inserted into a course of brickwork from the side of a layer of bricks and shoved in over a long distance, or else that special parts of a reinforcement stirrup be manually moved above the main reinforcement to obtain a firm anchoring and correct positioning of the main reinforcement.
It is an object of the present invention to provide a solution to said disadvantages, and to this end the reinforcement stirrup referred to in the introduction is characterized in that the arm of the hook is situated at a distance from the plane of the support section which is substantially equal to the thickness of the main reinforcement and this arm is open at the front of the masonry so that this main reinforcement can be pushed in from the front of the masonry until it comes into contact with the stem of the hook.
The arm of the hook preferably extends in a plane within which the plane of the stirrup leg also extends.
The positioning means used to position an essentially horizontally extended main reinforcement are, by their shape, designed in such a manner as to ensure an easy and accurate positioning of the main reinforcement without the necessity of difficult lateral insertion or moving manually special parts of the reinforcement stirrup.
As said, the reinforcement stirrup according to the present invention is designed so that the arm of the hook for the positioning of the main reinforcement lies at a distance from the plane of the support section that is substantially equal to the thickness of the main reinforcement. The hooks used for positioning the main reinforcement project for some distance above the plane of the support section; these hooks are preferably oriented in a direction parallel to that of the stirrup leg in the joint, and are therefore parallel to the joint in which said stirrup leg is located. The laid course of constructional elements thus includes a number of hooks projecting above the course itself and above the support sections resting against the course; an additional main reinforcement can in a simple manner be pushed in from the front of the masonry until it comes into contact with the stem of the hook, and this provides an excellent and easy positioning of the main reinforcement.
Many different materials can be employed for such a main reinforcement. One suitable material for this purpose is sold under the brand name Murfor(copyright), a reinforcement product of the applicant, N.V. Bekaert S.A., consisting of a steel wire construction comprising two longitudinally parallel wire components, these parallel wire components being connected with one another, for example, by means of zig-zag connecting wires secured at the tips to the wire-shaped reinforcing elements.
The reinforcement stirrup according to the invention is preferably provided with reinforcement stirrup positioning means for positioning the reinforcement stirrup in relation to a constructional element with which it cooperates.
Such reinforcement stirrup positioning means can be of many different kinds. The reinforcement stirrup positioning means according to the invention extend out from the plane of the support section and are situated below the plane of the support section, to the side of the stirrup leg.
Appropriately, the reinforcement stirrup positioning means comprise a protruding section whose end lies essentially in a plane in which at least one stirrup leg lies. The extremity is therefore situated below the plane of the support section and, with the placement of the reinforcement stirrup, the extremity comes into contact with a constructional element and the user can give this extremity a certain fixed position in relation, for example, to an identifying mark on each constructional element or, alternatively, to a vertical delimitation or some other aspect thereof. The reinforcement stirrups can be aligned perfectly in relation to each other by making the extremity of the protruding section of the reinforcement stirrup positioning means always hit the same point so that the insertion of a horizontally extending main reinforcement then presents no problems whatsoever, and a very solid result is obtained.
The reinforcement stirrup according to the invention is preferably made from a single length of wire, as will be discussed in the description.
The wire material for the reinforcement stirrup according to the invention can of course be of many different kinds, for example durable plastic such as Kevlar(copyright), nylon or polycarbonate or, for that matter, of metal, such as steel wire.
The reinforcement stirrup according to the present invention is preferably made of steel wire of a thickness of between 2 mm and 8 mm, and by preference between 3 mm and 5 mm.
Appropriately, the steel wire of a reinforcement stirrup according to the invention is provided with adhesion-promoting profiles such as corrugations, roughening, ripples, etc. Any profile that produces an improved adhesion between the reinforcement stirrup and the mortar used in the joints can be selected, and the professional will know which profile is best suited for which application.
In connection with the present invention, reference is also made to EP-B-0 603 517. This publication describes an elongated reinforcing element of the type described above and designated as the applicant""s product Murfor(copyright). Said elongated reinforcing element makes use of stirrups that extend into the joint between two constructional elements and that can easily be hooked onto any horizontally extending constructional element which has already been placed. There is then no question of any positioning effect being exerted by such stirrups used for positioning the horizontally disposed reinforcing element; nor, in fact, do such stirrups contribute to the direct transfer of forces acting on them to constructional elements surrounding the stirrups.
The invention further relates to masonry that is at least fitted with an essentially horizontally oriented main reinforcement which is positioned by means of reinforcement stirrups, such masonry being characterized by the fact that the reinforcement is positioned with the aid of reinforcement stirrups according to the invention, as described above.